1. Field of the Invention
The present invention relates to an integrated circuit package.
2. Description of Related Art
Integrated circuits (ICs) are typically housed within packages that are mounted to a printed circuit board. The printed circuit board assembly is typically located within the inner cavity of a computer housing. In operation, integrated circuits generate heat which can raise the temperature of the circuit. To avoid circuit failure, it is desirable to maintain the junction temperature of the integrated circuit below a predetermined value. For this reason it is desirable to remove the heat from the circuit and the IC package.
FIG. 1 shows a typical computer housing which has a fan 10 mounted to a front panel of the housing 12. The fan 10 generates a stream of air that flows across the integrated circuit packages 14. The airstream increases the heat transfer rate from the packages and removes the heat generated by the integrated circuits. The flow impedance of air flow through the chassis produces a large pressure drop and a corresponding reduction of the airstream flowrate, thereby reducing the effectiveness of the fan. It would be desirable to provide a more thermally efficient system for cooling integrated circuit packages, particularly packages which generate a significant amount of heat such as a microprocessor. Heatsinks using integral axially-directed fans are also currently used. This configuration is relatively inefficient due to the creation of a static air zone directly below the fan rotor. Moreover, attempts to increase heat transfer efficiency via more convoluted fin patterns are limited by the low air pressure that axial fans can produce.